Piston for internal-combustion engines.



R. E. RICH. PISTON FOR INTERNAL COMBUSTION ENGINES.

APPLICATION FILED IAN.20. I916- I Patented Nov 27, I917.

V all RALPH E. RICH, 0E CHICAGO, ILLINOIS.

, PISTON FOB, INTERNAL-COMBUSTIGN "ENGINES.

Specification of Letters Patent.

Patented Nov, 2?, WW3,

Application filed January 20, 1916. Serial No. 73,148.

To all whom it may concern:

Be it known that I, RALPH- E. RICH, a citizen ofthe United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pistons for Internal- Combustion Engines, of which the following is a specification.

My invention relates to the formation of the piston heads such as are used in internal combustion engines, as for instance, motors for automobiles, motor boats and the like, and has for its object the provision of a radiating and reinforcing structure which shall provide a large amount of radiating surface upon the head wall of the piston, and particularly shall provide for expansion and contraction of the piston uniformly, whereby more or less rapid distortion, and consequent irregula and unequal wear and deterioration are avoided, and which at the same time shall add strength and rigidity to the piston head. It is already well known to those familiar with such engines, that in some respects certain oys of aluminum are particularly suitable for the construction of pistons, and because of the great conductivity of aluminum and its alloys, and the consequent rapidity with which they absorb and become permeated with heat, and because of the relatively low temperature at which such materials lose their strength and hardness, it has been proposed and found necessary to provide reinforcements of radiating flanges to dissipate excessive heat and strengthen the piston. In all such pistons heretofore known, however, this. reinforcement has been connected to the cylindrical side wall of the piston at one or more points, and because of the high degree of expansion and contraction under extremes of heat and cold exhibited by aluminum and its alloys, a warping or distortion of the piston occurred in a short time and destroyed its usefulness. With the purpose of obviating this defect and realizing incidentally the advantages above mentioned. l have devised the new and improved form of piston hereinafter illustrated and described, the essential elements of my invention being poin out m the appended claims. I

In the drawings, Figure 1 illustrates-a as engine cylinder equipped with a referred form of my improved piston; ig.

2 is a bottom plan view of the inner side of the piston head-that is, the side from which the side wall of the trunk piston illustrated projects; and Figs. 3, at, 5, 6 and 7 similar bottom plan views of modified forms of piston in which the radiating and strengthening structures consist of diiferent arrangements of flanges or ribs.

My invention may be applied to explosion engines of various types and forms, in

till

which a reciprocating piston is arranged to manner, and also as formed with annular grooves arranged to receive the usual packing rings E.

The strengthening and radiating reinforcement of the piston head which constitutes the present invention, comprises, 111 the preferred form of embodiment shown in Flgs. 1 and 2 of the drawing, outer and inner circular flanges or ribs 15 and G rising from the inner side of the'head wall H of the piston concentric with its axis, the outer r1b F being entirely free from the side wall I of the piston. Radial cross walls J, in the present instance six in number, extending between the ribs F and G, and three symmetrically arranged radial walls K, meeting each other at the center and extending to points on the rib G intermediate the ends of adjacent walls J, are provided to brace and strengthen the annular flanges 1F and G, and increase the radiating surface of the-reinforcement. From the act that the reinforcing structure is wholly unattached to the sides of the piston, and also,

in some measure, because of the fact that its outer element is circular in form and concentric with the head wall H from whlch it rises, the stresses arising from the great extremes of temperature to which the piston is subject are symmetrically and uniformly v distributed on the piston head and adjacent roe is avoided and the portion of its side wall, so that distortion iston remains true in shape and wears uni ormly.

It will be'understood that while the exact arrangement of the Walls of the reinforcing structure in Figs. 1 and 2, and thus far described is particularly well suited to attain the ends in view, this arrangement may be varied within certain limits, the advantages before mentioned being mainly due to the fact that the outer reinforcing rib is entirely free from the side wall of the piston, and to some extent due to the circular concentric arrangement of the outer and inner ribs, and the symmetrical and staggered arrangement of the cross-members. In Figs. 3 to 7, I have illustrated various modified arrangements of the members of the radiating and reinforcing structure which will be understood without extended description. In Fig. 3 the central radial walls are omitted' and eight cross walls L connecting the circular ribs M and N are provided. The arrangement shown in Fig. 4 differs from that of Fig. 3 only in that the inner rib is of larger diameter, and a central pin or stalactite O is provided to aflord an in creased central radiating surface. lln Fig. 5 which is adapted for a larger piston than those previously described, four central radial walls P are provided, and eight con necting walls Q, extending between the outer and inner circular flanges R and S. In Fig. 6, which is adapted for a still larger piston three circular flanges T, U and V are provided, cross-walls W connecting the flanges T and U, and cross-walls X, arranged in staggered relation to the walls W, connecting the flanges V and V. In Fig. 7, I have shown a system of straight flanges XX and YY which form a central field of cr0ssr1bs, wholly detached from the side-Wall of the piston. It is obvious that still other modifications and arrangements are ossible without departing from the princip es and scope of my invention.

I claim:

1. A piston for explosive engines provided on the inner. surface of its head with connected radiating and strengthening members including at least two circular ribs concentric with the axis of the piston, and crosswalls connecting said ribs, the outermost rib being free from the side wall of the piston.

2. A piston for explosive engines .provided on the inner surface of its head with connected radiating and strengthening members including two circular ribs concentric with the axis of the piston, the outermost wall being free from the side Wall of the piston, cross-Walls connecting said ribs, and central radial walls extending from the axis of the piston to the inner wall.

3. A piston for explosive engines provided on the inner surface of its head with connected radiating and strengthening members including two circular ribs concentric with the axis of the piston, the outermost wall being free from the side wall of the .piston, radial cross-walls connecting said ribs, and central radial walls extending from the axis of the piston to the inner wall and arranged in staggered relationship with said cross-walls.

4. A piston for explosive engines provided on the inner surface of its head wall with a central field of connected. circumferential and cross walls constituting radiating and strengthening ribs and free from the side wall of the piston.

5. A piston for explosive engines provided on the inner surface of its head with a central field of connected circumferential and radial Walls symmetrically arranged and constituting radiating and strengthening ribs, said walls being free from the side wallof the piston.

RALPH E. RICH.

Witnesses LOUIS B. ERWIN, ROBERT DOBBERMAN. 

